Groundwater Circulation Wells

The remediation of a chlorinated hydrocarbons (CHC) contaminated aquifer always contains a risk, because of the possibility of uncontrolled downwards mobilization of the CHC into deeper parts of the aquifer. This scenario would be even more harmful to the environment. The application of well known remediation techniques for CHC as e. g. pump-and-treat is not useful because of its extremely long duration caused by the low solubility of CHC.

With a GCW it is possible to remove non-miscible liquids of higher density than water (DNAPL) from an aquifer. In order to remove dense non aqueous phase liquids (DNAPL) that have accumulated on the bottom of the aquifer, the GCW is operated in standard mode. The DNAPL is removed by means of a sensor-controlled, pneumatically-driven submersible pump. Thus it is made sure that just pure phase and no groundwater is extracted.

A GCW-system is capable of accumulating and extracting LNAPL during groundwater treatment. The amount groundwater passing through the GCW system can be adjusted according to the type of contamination and the well construction. Recovery of LNAPL floating on top of the groundwater can be achieved by using a GCW-Reverse flow system. Pure LNAPL product can be pumped to an on-site collection tank.

The chemicals (permanganates, peroxides etc.) required for the execution of ISCO are prepared above ground and fed into the groundwater by injecting it through a GCW. The required quantities should be determined by means of laboratory tests beforehand. To mix in hydrogen peroxide in moderate concentrations will stimulate the aerobic biological degradation. The radial-symmetric circulation fields permit more homogenous and more effective dispersion of chemicals in the subsoil than other hydraulic processing techniques.

The GCW-MPPE process is an in situ system for the remediation of groundwater contaminated with dissolved or dispersed aromatic, aliphatic, poly aromatic and halogenated hydrocarbons using a combination of a hydraulic controlled flushing/extraction system with a high efficient physical purification system based on macro porous polymer extraction.

The Multi-Functional Well (IEG MFW) has been implemented for the remediation of subsurface contamination caused by hydrocarbon spills. Four different remediation processes can be operated within the same well. At optimal efficiency of each remediation process, successive treatment of the capillary fringes, the vadose zone, and the aquifer can be accomplished. Each treatment process requires only simple modifications of the well configuration. Removal of the contaminants is done primarily through in situ air stripping.

The Reactive Well Technology (GCW-R) significantly enhances the ability to combine a dynamic hydraulic flow system (GCW) with different reactive treatment areas under anaerobic conditions.

The specially designed remediation wells enable easy change to the reactive materials, such as controlled-release carbon plus zero-valent iron (ZVI) or other reduced metals, which is the subject of our EHC technology.

IEG-vPRB In-situ Virtual Permeable Reactive Barrier with Overlapped Circulation Cells.
When a GCW is situated within the body of a groundwater contamination plume, this creates effective hydraulic control across a large diameter spherical capture zone within the aquifer. The polluted upstream groundwater is systematically captured by the GCW and treated in the well and within the aquifer.